Chapter 2 Reality Modern Metaphysics Leibniz Introducing Philosophy

Chapter 2: Reality Modern Metaphysics: Leibniz Introducing Philosophy, 10 th edition Robert C. Solomon, Kathleen Higgins, and Clancy Martin

Gottfried Wilhelm von Leibniz (1646 -1716) • Has been called the last of the universal geniuses • One of the inventors of calculus, father of modern formal linguistics, inventor of primitive computer, military strategist (may have influenced Napoleon), physicist thought to be the rival of Newton, great philosopher • Grew up in Leipzig but traveled considerably

• Spoke personally with most of the great philosophers of his time and debated with them constantly • His metaphysics is a combination of traditional theology and alternative to the physical doctrines of Newton • Had once been attracted to Newton’s philosophy but gave it up as “absurd” • Short Monadology (1714) is a summary of his mature metaphysical theories

The Principle of Sufficient Reason • There must be a reason for everything • Even God must have a reason for creating

Monads 1. The Monad, of which we will speak here, is nothing else than a simple substance, which goes up to make composites; by simple, we mean without parts 2. There must be simple substances because there are composites; for a composite is nothing else than a collection or aggregatum of simple substances 3. Now, where there are no constituent parts there is possible neither extension, nor form, nor divisibility. These Monads are the true Atoms of nature, and, in fact, the Elements of things — Leibniz, Monadology

• • • Monad: a simple substance that cannot be divided Every composite is made up of simple substances, but if the substances were extended in space, they would be further divisible into other simple substances Leibniz decides then that monads must be immaterial and have no extension; he is a pluralist Monads can be created or destroyed but not by any “natural” means; they can be created or destroyed only “all at once” Notice that compounds of monads can be created or destroyed “naturally”

Principle of the Identity of Indiscernibles • No two monads can have all the same properties – Each monad must be different from every other in at least some respect – Prop. 9 • Why believe this? – Because of the Principle of Sufficient Reason • Even God has no reason to create an exact duplicate

1. Interaction of Substances • Monads only apparently interact with each other. The apparent interaction between monads must really be changes in the perceptions of the monads themselves • What is ultimately real is the perceiving monad. Distinguishes between perception and consciousness—perception is experience, and consciousness (the ability to be reflective) is shared by only a few monads • Bodies only seem to interact; in fact, it all happens with each monad, programmed and created by God in pre-established harmony

2. Space and Time • Space and time are not substances. Monads do not exist in space or time • Famous disagreement of Newton and Leibniz: Newton’s theory presupposes some permanent container, called absolute space, but Leibniz rejected this idea • The idea that space could exist apart from all things in it, perhaps even entirely empty, would mean that it makes sense to talk about movement or location in space even when there is not anything in space

• Leibniz insisted that space is relative because it is absurd to think of it as being not relative • Newton believed in absolute time, time as existing apart from anything happening in it, but Leibniz rejected this because certain kinds of questions can’t be answered by this account • “When did the universe begin? ” The question itself seems absurd

3. God and the Universe • The Principle of Sufficient Reason has a further implication: it serves as a principle of divine ethics • Among the various possible worlds, God chooses the most perfect, “the best of all possible worlds”